I used a CoolTech harness for my 2008 JK, but the Mopar one seems a good choice.
Here is the CT link:
JK Tow Harness Deluxe Kit - CoolTechLLC
Lots of folk seem to have trouble with the CT, but I don't know why.
I run a charge wire from the MH to the JK battery. You pull the M1 fuse as noted in the CT instructions and turn the ignition key to unlock the column.
The charge wire was part of the US Gear brake system I installed.